1. Field of the Invention
The present invention relates to an ink-jet head which ejects ink to a record medium.
2. Description of Related Art
An ink-jet head included in an ink-jet printer or the like distributes to pressure chambers ink supplied by an ink tank, and selectively applies pulsed pressure to each of the pressure chambers so that ink is ejected through nozzles communicating with the respective pressure chambers. An actuator unit in which piezoelectric sheets made of a piezoelectric ceramic are put in layers may be employed as a means for selectively applying pressure to the pressure chambers.
This type of ink-jet head is exemplified by one which has an actuator unit including a piezoelectric sheet that extends over pressure chambers, individual electrodes that correspond to the respective pressure chambers, and a common electrode that is opposed to the individual electrodes with the piezoelectric sheet interposed therebetween (see Japanese Patent Unexamined Publication No. 2003-311953). Each of the individual electrodes includes a main electrode portion and an auxiliary electrode portion, and is electrically connected to a flexible printed circuit (FPC) configured as a wiring board. The main electrode portion is formed at a position opposed to a corresponding pressure chamber. The auxiliary electrode portion receives voltage from the outside. The FPC has terminals respectively corresponding to the auxiliary electrode portions. Each terminal is bonded to a corresponding auxiliary electrode portion with a solder.